1. Field of the Invention
The present invention relates to liquid ejection devices configured to eject liquid droplets.
2. Description of Related Art
Known liquid ejection devices, e.g., inkjet printers, are configured to removably mount thereon liquid cartridges containing liquid for use in liquid ejection heads. A known inkjet printer ejects ink on various recording mediums to form a desired text, image or combination thereof. The inkjet printer is configured to removably mount thereon liquid cartridges containing different color inks.
There are two types of ink cartridges to be mounted to a known inkjet printer, as described in Japanese Laid-Open Patent Publication No. 2001-353880. One is an initial ink cartridge packed with a new inkjet printer. The other is a replacement ink cartridge that users will purchase at retailers separately from an inkjet printer when ink in the ink cartridge mounted to their inkjet printer runs out. The initial ink cartridge contains a greater initial amount of ink than the replacement ink cartridge contains because a partial amount of ink contained in the initial ink cartridge is to be initially introduced to e.g., an inkjet head and/or a sub-tank of the printer, before the printer is initially used.
It will be rare but may happen that an initial ink cartridge is replaced not with a replacement ink cartridge but with another initial ink cartridge, which may be possibly placed on the market without being packed with a new inkjet printer for some reasons. Thus, users may unintentionally mount the initial ink cartridges on their printers more than once.
When an ink cartridge is replaced with new one after ink has been initially introduced to an inkjet head of an inkjet printer, mounting of an initial ink cartridge, instead of a replacement ink cartridge, may cause problems to the inkjet printer, due to differences in initial amounts of ink contained in the initial ink cartridge and the replacement ink cartridge. For example, an initial ink cartridge, which contains a greater initial amount of ink than a replacement ink cartridge contains, is mounted to the inkjet printer, a level of the ink in the initial ink cartridge is positioned higher, as compared with the case when a replacement ink cartridge is mounted to the inkjet printer. This causes higher pressure, e.g., hydraulic head pressure, to be applied to nozzles of an inkjet head, than a specified design value and the higher pressure may cause meniscuses in the nozzles to break.